<!DOCTYPE html>
<html lang='en'>

<head>
   <meta charset='UTF-8'>
   <meta http-equiv='X-UA-Compatible' content='IE=edge'>
   <meta name='viewport' content='width=device-width, initial-scale=1.0'>
   <title>Document</title>
   <script src='../vue.js'></script>
</head>

<body>
   <div id='app'>
      <h1>{{msg}}</h1>
   </div>
      <script>
         const vm = new Vue({
         data: {
            msg: 'Hello Vue!!!',
            
         }
         })

         // vm.$mount( [elementOrSelector] )
         // 把vm的挂载单独书写出来(除了我们可以自由选择挂载时机以外,和el配置项没有其他的区别)
         setTimeout(() => {
            vm.$mount = ('Hello World!!!')
         }, 2000)

         // 下边的写法也比较常见
         /* new Vue({
            data: {
            msg: "hello Vue"
            }
         }).$mount("#app") */
            </script>
</body>

</html>